1. Field of the Invention
The present invention relates to a cooking apparatus, and more particularly to a cooking apparatus, which includes a socket for power supply provided at a rear wall of its cooking cavity and a tray having a heater therein so as to cause the tray to generate heat by the heater, thereby improving heating efficiency.
2. Description of the Related Art
Generally, a cooking apparatus includes a cooking cavity to receive foods to be cooked, and a heating device installed in the cooking cavity or in an additional compartment isolated from the cooking cavity. For example, a microwave oven, which is a kind of cooking apparatus, includes a cooking cavity defining a space for cooking foods therein, and a machine room isolated from the cooking cavity having a magnetron generating microwaves. The microwaves are then introduced into the cooking cavity to cook the food.
In microwave ovens, where cooking is performed by only the microwaves from the magnetron, it is difficult to achieve a satisfactory cooking result because food is not evenly irradiated with the microwaves due to factors such as water content, distribution, and size of the food. Further, it is impossible to perform various kinds of cooking. To overcome such problems in conventional microwave ovens, a microwave oven has been proposed, in which the cooking cavity includes upper and lower heaters, to quickly and evenly cook food in the cooking cavity by heat generated from the upper and lower heaters as well as microwaves generated from the magnetron and to allow various kinds of cooking to be performed.
In the microwave oven with the upper and lower heaters, when the upper and lower heaters are turned on after a tray, on which food is placed, is received in the cooking cavity between the upper and lower heaters, the food can be cooked by heat generated from the upper and lower heaters, as in a grill oven.
However, in a conventional cooking apparatus provided with a plurality of heaters in its cooking cavity, the cooking cavity is not only reduced in its capacity but also complicated in its structure, thereby precluding efficient employment of the cooking cavity and increasing production cost and time.
In addition, in the conventional cooking apparatus, a tray in a cooking cavity is separated from a lower heater, so that heat generated from the lower heater must be transmitted to the food through the tray. Thus, heating efficiency is decreased and sufficient heat energy cannot be transmitted to a lower surface of the food, thereby increasing electric power consumption. Furthermore, since the amount of heat energy transmitted to upper and lower parts of the food are different from each other, the food must be periodically turned over to evenly cook upper and lower parts of the food, thereby causing the user inconvenience. Moreover, since a temperature at a part of the microwave oven around the lower heater becomes very high, a cooling fan operating at a high speed must be provided in the microwave oven to cool the heated part, thereby causing unpleasant noise due to the high-speed operation of the cooling fan.
Additionally, since a tray disposed to be spaced from a lower heater of the conventional cooking apparatus has uneven temperature distribution between its upper surface and its lower surface facing a lower heater, food placed on the tray is not evenly cooked.